gravely



Pntent'ed Nov. 4, 1919.

Adhesive. film compris-m7 polgmerzcd Chinese Wood oll- UNTTED sTATEsPATENT oEEIoE.

JULIAN S. GRAVELY, OF NEW HAVEN. CONNECTICUT, ASSIGNOR TO WINCHESTERREPEATING ARMS CO., OF NEW HAVEN, CONNECTICUT, A CORPORATION.

SHOT-SHELL.

Specification of Letters Patent.

Patented Nov. 4, 1919.

Applicatie med June 14, 191s. serial No. 304,344.

and State of Connecticut, have invented a new and useful Improvement inShot- Shells; and l do hereby declare the following to be a full,clear,"A and exact description of the same.

My invention relates to an improved pape-r tube for use in themanufacture of paper shot-shells, the object being to produce a smooth,hard and tough tube of superior' resistance to moisture, and of atexture which adapts it to hold its crimp. A further object of theinvention is to produce such a superior tube without resorting to anyoperations in addition to those commonly used in the production of papershot- .shell tubes.

Vith these'ends in view, my invention consists in a paper shot-shelltube characterized by a plurality of superimposed coils of paper andco-extensive interposed coils. of an adhesive non-hygroscopic filmadhering and Yconsolidating the respective coils of paper, the said filmcontaining polymerized Chinese Woodoil.

My invention further consists in a paper shot-shell tube having certaindetails of con struction as Will be hereinafter described and pointedout in the claims, reference being had to the accompanying drawing, inwhich the figure is an enlarged View in transverse section of a. papershot-shell tube produced in accordance with my invention.

In carrying out. my invention, I wind' a sheet of suitable paper upon amandrel after the paper has had applied to one of'its faces a continuousfilm of a paste containing Chinese wood or tung-oil. The moist tuber,

is then dried, preferably in the air, after which it is subjected toheat for a sufficient length of time to polymerizethe Chinese wood oil.The tube thus producedconsists of a pluralitv of superimposed coils ofpaper respectively separated from each other but bound together andconsolidated by co-ex-. tensive coils of a continuous non-hygroscopieadhesive film. The polymerization of the Chinese, wood oil in the pastemakes the tube resistant to moisture, makes it hard and smooth withoutbrittleness, and of a texture which adapts it to hold its crimp. Thesurface, smoothness of the tube is such that it passes through thesizing' dies Without the employmentof the lubricant ordinarily found tohe necessary to prevent the exposed fibers of the outer coil of thepaper from adhering to the burnished surfaces of the dies.A After beingsized, the tubes are.

dipped in a bath of molten paraflin, or a;

bath consisting of a mixture of paraflin,' petrolatum, or other sultablecompound for' the purpose of impregnating the fibers of the paper so asto render it immune to powder-burns or gas-leaks, as well as to make thetube additionally moisture-resistant, though the primary object ofimmersing the tubes in a`bath of parafin or equivalent substance, is totreat their interior surfaces in' such a manner as to preventpowder;burns and gas-leaks which occur, if Vat all, from the inside ofthe tube outward. In this conneetion it may be said that whilethe tubeis made resistant to moisture by the nonhygroscopie adhesive film coiledbetween the paper coils, the tube'is made proof against poW-,

der-burns and gas-leaks by the impregnation of the fibers vof therespective coils. I am aware that paraflin as used in the manufacture ofpaper shot-shell tubes, is ordinarily considered as vmerely aWater-proofing constituent. It is true that paraffin' does aid inwater-proofing, but paraffin is of even greater importance as used inpaper shotshells in preventing powder-burns which originate solely onthe inside of the tube and which are likely to occur if the shells arefired in a liot gun. -The fact that paraffin is a great deterrent ofpowder-burns is more readily demonstrated than explained. It is,however, conceived that-it so actsfor the reason that being liquefied atvthe instant of explosion, it envelopsthe fibers of the paper in asmothering fluid and prevents the access of sufficient oxygen thereto tosu port combustion.

aper shot-shel-ls made from such tubes are -found to stand up underftheendwisenate comple-ted paper shot-shell tubes by l l l.

their immersion in solutions containing polymerizzlblc oil, a processless effective and less reliable than my'improved method of introducingTthe polymerizable oil into the paste used to cement the plies ot' thepaper together, for a number of reasons, aniomgr which I, may mentionthe certainty I secure of the even distribution of the pol ymerizable`oil throughout the entire structure otl the` tube due to the fact thatthe oil is mechanically introduced with certainty and uniformity betweenthe plies ot the paper. whereby I eliminate the factors of uncertaindistribution due to variations in the absorbative capacity of the paperitself, to variations in the tension under which the tubes are.initially wound, and to variations in the moisture-content of thecompleted tubes when placed in the bath due to variations in thehumidity of the atmosphere. Moreover serious objections exist to the`useof a bath of polymerizable oil which must be maintained atan elevatedtemperature to enable it to be driven into the completed tubes. Onaccount of the elevated temperature at which the bath must bemaintained, the polymerization of the oil in the bath may take placeprior to the introduction of the tubes into it. Thus, if a. bathcontaining polyinerizable oil is .kept over from day` to day at anelevated temperature, it is obvious that a considerable variation in itscontent of polyiiicrizable oil will result with the effect of makingvariations in the amount of polymerizable oil actually taken up by thetubes causing the bath-impregnation process y to be attended withuncertainty, whereas it is desirable to secure the highest possibleuniformity in the amount of polymcrizable oil in the tubes. All theseobjections are overcome by my improved method of intro- ,ducing thepolymerizable oil into the paste 'the-spccific character of which may becontrolled with more ease and certainty than a bath. I `Urthermore. asuperficially applied ooating'of polymerizable oil will unavoidably varyin thickness owing to variations in'/ temperature, causing correspondingvariations in the. viscosity of the bath solution. The above objectionsapply to processes depending on` impregnation in bat-hs. As to all'processes of coatingpaper shot shell tubes with polymerizable oil byspraying or paint-ing, they are open to the objection that they involvea separate group of treatments j entailing,r additional time and laborwhich must be added to the cost of the tubes. The coating process,moreover, is 'superficial in character, variableA in'result, andobjectionable in that the coating being superficial rather thanintegral, may be seriously impaired by abrasion, to that extent reducingthe protection aimed at. These results, as

stated. l concciviI to bc due to the tact that the pol \'merizuble oilwhen used in the paste uniformly distributed mechanically tlix'ui;'liolu the structure ot' the paper tubes. whereas tubes dependentupon the permeation of the fibers ot' the paper by waterproofingcompounds. vary in density with variations in the. compound and the heatunder which it is applied. as well as in variations in the density ofthe paper slice-ls. My improvedshells may be carried in the pocket of ahunter and subjected to lone` continued abrasion without having' theirexterior surface abradcd or roug'hcned so as to prevent them fromfunctioning in his gun. iVhile l do not limit myscll to thc employmentof any specific paslc l'or the prosecution of' my invention, lA havesecured excellent results by the use ot' a paste made by boiling starchand water until nearly the-required consistency has been secured, andthen adding from lf/ to 16234 of Chinese wood oil and continuingtheeooking`r process Witlrstirring. until thorough emulsification hastakenplace. i

I claim l. As a new article'of manufacture, a paper tube for use in themanufacture of papel shot-shells, consisting of' a plurality of coils ofpaper separated by co-extensive interposed coils of a non-hygroscopicadhesive film which binds the, coils of the paper together andconsolidates them and makes the tube resistant to moisture. the saidfilm containing Ipolymerized (.hincse wood oil.

As a new article of manufacture, a paper tube f'or use in themanufacture of paper shot-shells. consistiiugT of a plurality of coilsof paper separated by cti-extensive able paper, then ceiling the paperinto a Y tube, then subjecting the tubo to heat for polymerizing theChinese wood oil contained in the paste, then' sizing the tube, andfinally subjecting it to a bath of fire-proofing compound for theimpregnation of its fibers.

In testimony whereof, 1 have signed this specification in the presenceof two subscribing witnesses.

JULIAN s. ointvninf.

Witnesses:

DANIEL H. VEADER, ERIK S. PALMER.

